青海高原冻土退化驱动因素的定量辨识

利用G IS技术、主成分分析和关联度等定量方法,分析了1981~2000年青海高原冻土退化的空间特征。研究表明:1981年以来青海高原冻土呈现出多年冻土减少、季节冻土增加的总体退化趋势,其中季节冻土由1981~1985年占全省总面积的37.5%增加到了1996~2000年的41.7%;在人为活动和气候变化对季节冻土退化的驱动作用当中以人类活动的作用更为显著,气候变暖是造成季节冻土退化的主导气候因素。

Quantitative Identification of Driving Factor of Frozen Ground Degeneration in Qinghai Plateau

By using GIS technique and principal component analysis as well as association limitation,the spatial characteristics of frozen ground degeneration in 1981-2000 was analyzed,and different function of human activity and natural factor upon frozen ground degeneration was identified,and the main causes of frozen ground degeneration were finally confirmed.The results show that the multi-year frozen ground in Qinghai Plateau has been decreasing but seasonal frozen ground increasing since 1981,among which the seasonal frozen ground increased to 41.7% in 1996-2000 from 37.5% in 1981-1985;comparing the driving function of human activity with climate change upon frozen ground degeneration,the former one is much more significant,and the association sequence of climate factor and frozen ground degeneration is mean temperature,annual total cloudiness,annual low-level cloudiness,annual sunshine duration,annual precipitation and annual snow-cover hours,which shows that the climate warming is the main cause of frozen ground degeneration.